In recent years, in vehicles such as automobiles, the technology development of the advanced driving assistant system (ADAS) or automated driving is being actively pursued, and the subject of driving is about to change from a person to a machine. The driving control technology such as the ADAS or automated driving can be mainly classified into three functions, namely, a recognition function, a determination function, and a control function. The recognition function enables recognition of the state of the vehicle based on a variety of sensing information obtained by an accelerator sensor, a vehicle velocity sensor, a GPS sensor, a vehicle-mounted camera, and a lidar apparatus. The determination function enables determination of the necessary vehicle control based on the recognition result obtained by the recognition function and based on the current control status. The control function enables controlling the vehicle based on the determination result obtained by the determination function.
The recognition function, the determination function, and the control function of the ADAS or automated driving are implemented using a vehicle-mounted device (a vehicle-mounted system) mounted in the vehicle. However, the sensors or the LSI circuits used in the vehicle-mounted device not only differ among the vehicle vendors but also differ among the vehicle types. Hence, the capability of each function differs for each vehicle type. For example, when the brake performance of a vehicle type A is different from the brake performance of a vehicle type B, then the control timings differ due to different braking distances. Moreover, even in the same vehicle type, if the vehicle-mounted device is altered, the performance thereof also differs. Moreover, depending on the skills of the driver and the surrounding environment, the control stability also happens to change.
The information related to the vehicle performance or the control stability can be useful in implementing appropriate vehicle control using the ADAS or automated driving. Particularly, the information related to the surrounding vehicles that are running around (in the vicinity of) the concerned vehicle serves as important information. For example, when a low-performance vehicle or a vehicle having unstable behavior (control) is present in front of the concerned vehicle, it becomes possible to perform control such as expediting the braking timing. For that reason, there is a demand for a mechanism for reflecting the performance of the surrounding vehicles and the control stability (in the following explanation, the concept including those points is called “degree of reliability”) in the vehicle control.